Material-screening device



Nov. 30, 1926.

F. N. WILSO'N MATERIAL scnnsnme DEVICE Filed June a, 1926 I. m .r

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w Fw Z E 5 h Patented Nov. 30, 1926.

FRANK WIFS ON, 0F WEBSTER GROVES, MISSOURI.

MATERIAL-SCREENING DEVICE.-

epplication filed June 5,

My invention relates to improvements in screening devices and particularly to devices for screening coal.

In the usual practice of screening coal, the pieces of coal together with the pieces of slate and the like found, therewith, are screened for the various sizes, it being understood. that it is the desire to screen out all of the slate if possible. The usual practice is. to load the mined material including the slate, onto inclined screens, these screens being either stationary or rocked to and fro, and as the material: travels, along the screen, all of the pieces under a certain size (determined by the size. ofthe screen openings) are supposed tov fall through the screen, while those pieces over, the desired size are, discharged at the lower end of the screen;

it is a well-known tact, however that such a desideratum is not fullyreached in these types of screens. The openings of the screens tend to clog during the passage or the coal thereover and the pieces of slate are usually oi": such a shape that they slide along the screen without falling. through the screen openings. Although the coal it self, as mined, breaks away from the vein in lumps and cubes, the pieces of slate break away in slabs or layers on account of their peculiar line of cleavage. Hence it is easy to see that many of the. pieces of slate, on account of their flat, shape, do. not. stand upon edge as they move down the screen, but tend to slide th' erealong on. their fiat sides, and hence are not screened out.

The main object of my invention is to provide a screen wherein means are provided for positively turnlngthe pieces of material that areupon the screen upon edge rend during their passage over the screen, whereby those, pieces of material, especially slate, that are thin and flat will be tilted to fallthrough the screen openings, drop} ping to the refuse pile, and will not be dis charged at'the delivery end of the; screen,

Another ohject'otmyinventionis'to pro} vide" a" screen ofjthe k nd described, Wherein l the S means t ibej pr vely actu the pl ecesof'linater l as e'y" passjalongfthe len ti of the self 1v. advancing. thep ces. "to WE-"li t int. 1,

cram will remain stationary and upfi h by, means" at bolts 6, 'tli'ese nee weusrarming, a'frough'or chute uponiiwl 1926. Serial No. 113,860.

them or turn them upon edge so that the thinner pieces will fall through the open ings of the stationary screen.

Another object of my invention is to pro vide a screen of the kind described wherein the screen proper will be formed of. a plurality of longitudinally extending bars, lip-endedto form whatniay be termed a grizzly, this type of structure beings);- tremely. durable in service. Other objects of my invention include the provision of means whereby this grizzly may be adjusted relatively to the supporting framework therefor so as to vary the degree of inclination of the screen, and also the provision of means whereby the spacing between the separate bars of the screen may be varied oradjusted so as to space for screeningv different sizes of material.

The invention has among its other objects the provision of a screen of the kind described, which shall be simple, convenient, economical, reliable, and efiicient and satisi'actory foruse wherever found applicable.

Many other objects and advantages of the construction herein shown and described will be obvious to those skilled in the art to which this invention appertains, from the disclosures herein given.

To this end, my. invention consists in the novel construction, arrangement, and combination of parts herein shown and, described, and more particularly pointed out in the claims.

In the drawings, wherein like parts are indicated by like reference characters throughout th views,

Figure I is a side elevation, certain of the parts being broken away in order to show theinvention more clearly;

"Figure II is a top plan view otthe same; and

Figure III is, an end elevation thereof.

In the. drawings, wherein I have illus tinted the prefercdr embodiment of my invention, 'A indicates a supporting frameworlniipon"whichtlieiscreening device B is adapted'to bemounted, the forward and rear uprights of the framework being, in-

d at '1 mac; 'TheTsideflwalls 3 of the s senate secured atftheirl ends tothe V are loaded t m ing. In order to reinforce. the chute liners of steel, or wear plates, are provided as at- 4, these plates being suitably connected to the side walls 3 and depending downwardly therefrom.

The screen proper consists of the plurality of bars 5, these bars being spaced apart and extending longitudinally paral- .lel to each other to form a grizzly. Tierods 7 pass through the wear plate a and the bars 5, one rod at each end of the screen, and upon these tie-rods are arranged rela tively thin washers, so as to adjustably space the bars apart, these washers being indicated at 8.

The spaces or openings between each pair of bars are indicated at 9, and the other spaces between the bars, namely the spaces between the adjacent pairs of bars are indicated at 10, the latter spaces being those through which the pieces of material under a certain size are intendedto fall, while the rest of the material moves down the screen to the discharge end.

In order to provide for the adjustment of the degree of inclination of the screen a series of openings 12 may be provided in the lower uprights 1, as shown, and through which the bolts 6 may pass.

A. series of movable bars 13 are arranged to cooperate and coact with the stationary bars 5, in a manner to be more clearly hereinafter described, one of these bars 18 being interposed in one or more of the spaces 9 so as to be vertically slidable therethrough. These movable bars are connected together so as to be actuated in unison, the tie-rods 14 passing through the bars 13, one tie-rod at each end of the screen. Thin washers, similar to those between the bars 5, space the bars 13 apart adjustably.

The forward tie-rod 1 1- is pivotally connected to the lower ends of a pair of links l-l5', one pair of links at each end of the tie-rod as shown, the links being pivotally connected at their upper ends to the wear plates 4 so as to be suspended therefrom at the points 1. I

The rear tie-rod has a pair of links 16 16 pivotally connected at its ends, and in the embodiment shown, the links 16 of each pair are longer than the links 16 and pro- 'ect downwardly therebelow, said longer inks being pivotally connected at their ower ends to the yoke 18. All of the links 16-46 are pivotally connected at their upper ends to the wear plate 1 so as to suspend therefrom in the same manner as the forward links -15.

The bars 18 are preferably of a greater depth than the bars 5 and are so positioned that when the former are in their lowermost position they will have their upper edges substantially flush with the upper edges-of the fixed bars 5, lit is obvious that, as the yoke 18 is moved forwardly, the links carrying the movable bars will swing about their pivotal points 17, thus swinging the movable bars upwardly and forwardly relatively of the fixed bars, the movable bars always being parallel with the fixed bars in their entire path of movement. The movable bars'engage with any pieces of material that may happen to be upon the screen, gives them a forward and upward movement, and tilts them so as to turn them upon edge or end, and causes the thin pieces to fall through the openings 10 of the screen.

The yoke member 18 may be given a reciprocatory movement by any desired means, as for example by attaching its rear end to a crank (not shown).

The material is loaded upon the chute adjacent the rear thereof, and as the movable bars are oscillated they engage with the pieces of material with a forward and lifting movement. The material is thus given a step-by-step movement down the screen, and those pieces smaller than the spacing between the bars of the screen are screened out and are dropped to the ground, while the larger pieces of usable material continue in their travel toward the discharge end of the screen, The pieces of slate are screened out exceedingly well, because they are up-ended or tilted intermittently, and as they are very much thinner than broad they will easily fall through the openings of the screen when tilted.

Thus it is seen that I have provided a device, which although particularly adapted for screening the smallest usable sizes of coal, yet, may be efficiently used for screening of larger sizes of coal and for any other materials.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence I do not wish to be understood as limiting myself to the exact construction, form, arrangement and combination of parts herein shown and described, or uses mentioned, except as limited by the claims. 7 What I claim as new and desire to secure by Letters Patent is:

I 1. A device of the kind described, com prising a plurality of fixed bars forming a screen along which pieces of material are adapted to be moved, movable bars arranged parallel to and intermediate alternate pairs cnlyof the fixed bars, means for intermittently actuating the movable bars forwardly and upwardly of the fixed bars to engage with the pieces of material.

2. A device of the kind described, comprising a plurality of spaced, longitudinally-extending bars, forming a screen inclined downwardly toward'its discharge end, and adapted to receive pieces of material thereupon, movable bars arranged parallel With and substantially filling the space between intermediate of pairs of adjacent fixed bars and normally having their upper edges substantially flush with the upper edges of the fixed bars, and means for intermittently actuating said movable bars forwardly and upwardly of said fixed bars to advance the pieces of material along the screen and tilt them to cause some of 10 the pieces to fall between the spaces between adjacent fixed bars.

FRANK N. lVILSON. 

